Subversion Repositories Applications.papyrus

if(!dojo._hasResource["dojox.data.QueryReadStore"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.

dojo._hasResource["dojox.data.QueryReadStore"] = true;

dojo.provide("dojox.data.QueryReadStore");

dojo.provide("dojox.data.QueryReadStore.InvalidItemError");

dojo.provide("dojox.data.QueryReadStore.InvalidAttributeError");

dojo.require("dojo.string");

dojo.require("dojo.data.util.simpleFetch");

dojo.declare("dojox.data.QueryReadStore", null, {

	/*

	//	summary:

	//		This class provides a store that is mainly intended to be used

	//		for loading data dynamically from the server, used i.e. for

	//		retreiving chunks of data from huge data stores on the server (by server-side filtering!).

	//		Upon calling the fetch() method of this store the data are requested from

	//		the server if they are not yet loaded for paging (or cached).

	//

	//		For example used for a combobox which works on lots of data. It

	//		can be used to retreive the data partially upon entering the

	//		letters "ac" it returns only items like "action", "acting", etc.

	//

	//  note:

	//      The field name "id" in a query is reserved for looking up data

	//      by id. This is necessary as before the first fetch, the store

	//      has no way of knowing which field the server will declare as

	//      identifier.

	//

	//	examples:

	//		// The parameter "query" contains the data that are sent to the server.

	//		var store = new dojox.data.QueryReadStore({url:'/search.php'});

	//		store.fetch({query:{name:'a'}, queryOptions:{ignoreCase:false}});

	//

	//		// Since "serverQuery" is given, it overrules and those data are

	//		// sent to the server.

	//		var store = new dojox.data.QueryReadStore({url:'/search.php'});

	//		store.fetch({serverQuery:{name:'a'}, queryOptions:{ignoreCase:false}});

	//

	//	todo:

	//		- there is a bug in the paging, when i set start:2, count:5 after an initial fetch() and doClientPaging:true

	//		  it returns 6 elemetns, though count=5, try it in QueryReadStore.html

	//		- allow configuring if the paging shall takes place on the client or the server

	//		- add optional caching

	//		- when the first query searched for "a" and the next for a subset of

	//		  the first, i.e. "ab" then we actually dont need a server request, if

	//		  we have client paging, we just need to filter the items we already have

	//		  that might also be tooo much logic

	*/

	url:"",

	requestMethod:"get",

	//useCache:false,

	// We use the name in the errors, once the name is fixed hardcode it, may be.

	_className:"dojox.data.QueryReadStore",

	// This will contain the items we have loaded from the server.

	// The contents of this array is optimized to satisfy all read-api requirements

	// and for using lesser storage, so the keys and their content need some explaination:

	// 		this._items[0].i - the item itself

	//		this._items[0].r - a reference to the store, so we can identify the item

	//			securly. We set this reference right after receiving the item from the

	//			server.

	_items:[],

	// Store the last query that triggered xhr request to the server.

	// So we can compare if the request changed and if we shall reload

	// (this also depends on other factors, such as is caching used, etc).

	_lastServerQuery:null,

	// Store a hash of the last server request. Actually I introduced this

	// for testing, so I can check if no unnecessary requests were issued for

	// client-side-paging.

	lastRequestHash:null,

	// If this is false, every request is sent to the server.

	// If it's true a second request with the same query will not issue another

	// request, but use the already returned data. This assumes that the server

	// does not do the paging.

	doClientPaging:true,

	// Items by identify for Identify API

	_itemsByIdentity:null,

	// Identifier used

	_identifier:null,

	_features: {'dojo.data.api.Read':true, 'dojo.data.api.Identity':true},

	constructor: function(/* Object */ params){

		dojo.mixin(this,params);

	},

	getValue: function(/* item */ item, /* attribute-name-string */ attribute, /* value? */ defaultValue){

		//	According to the Read API comments in getValue() and exception is

		//	thrown when an item is not an item or the attribute not a string!

		this._assertIsItem(item);

		if (!dojo.isString(attribute)) {

			throw new Error(this._className+".getValue(): Invalid attribute, string expected!");

		}

		if(!this.hasAttribute(item, attribute)){

			// read api says: return defaultValue "only if *item* does not have a value for *attribute*."

			// Is this the case here? The attribute doesn't exist, but a defaultValue, sounds reasonable.

			if(defaultValue){

				return defaultValue;

			}

			console.log(this._className+".getValue(): Item does not have the attribute '"+attribute+"'.");

		}

		return item.i[attribute];

	},

	getValues: function(/* item */ item, /* attribute-name-string */ attribute){

		var ret = [];

		if(this.hasAttribute(item, attribute)){

			ret.push(item.i[attribute]);

		}

		return ret;

	},

	getAttributes: function(/* item */ item){

		this._assertIsItem(item);

		var ret = [];

		for(var i in item.i){

			ret.push(i);

		}

		return ret;

	},

	hasAttribute: function(/* item */ item,	/* attribute-name-string */ attribute) {

		//	summary:

		//		See dojo.data.api.Read.hasAttribute()

		return this.isItem(item) && typeof item.i[attribute]!="undefined";

	},

	containsValue: function(/* item */ item, /* attribute-name-string */ attribute, /* anything */ value){

		var values = this.getValues(item, attribute);

		var len = values.length;

		for(var i=0; i<len; i++){

			if(values[i]==value){

				return true;

			}

		}

		return false;

	},

	isItem: function(/* anything */ something){

		// Some basic tests, that are quick and easy to do here.

		// >>> var store = new dojox.data.QueryReadStore({});

		// >>> store.isItem("");

		// false

		//

		// >>> var store = new dojox.data.QueryReadStore({});

		// >>> store.isItem({});

		// false

		//

		// >>> var store = new dojox.data.QueryReadStore({});

		// >>> store.isItem(0);

		// false

		//

		// >>> var store = new dojox.data.QueryReadStore({});

		// >>> store.isItem({name:"me", label:"me too"});

		// false

		//

		if(something){

			return typeof something.r!="undefined" && something.r==this;

		}

		return false;

	},

	isItemLoaded: function(/* anything */ something) {

		// Currently we dont have any state that tells if an item is loaded or not

		// if the item exists its also loaded.

		// This might change when we start working with refs inside items ...

		return this.isItem(something);

	},

	loadItem: function(/* object */ args){

		if(this.isItemLoaded(args.item)){

			return;

		}

		// Actually we have nothing to do here, or at least I dont know what to do here ...

	},

	fetch:function(/* Object? */ request){

		//	summary:

		//		See dojo.data.util.simpleFetch.fetch() this is just a copy and I adjusted

		//		only the paging, since it happens on the server if doClientPaging is

		//		false, thx to http://trac.dojotoolkit.org/ticket/4761 reporting this.

		//		Would be nice to be able to use simpleFetch() to reduce copied code,

		//		but i dont know how yet. Ideas please!

		request = request || {};

		if(!request.store){

			request.store = this;

		}

		var self = this;

		var _errorHandler = function(errorData, requestObject){

			if(requestObject.onError){

				var scope = requestObject.scope || dojo.global;

				requestObject.onError.call(scope, errorData, requestObject);

			}

		};

		var _fetchHandler = function(items, requestObject){

			var oldAbortFunction = requestObject.abort || null;

			var aborted = false;

			var startIndex = requestObject.start?requestObject.start:0;

			if (self.doClientPaging==false) {

				// For client paging we dont need no slicing of the result.

				startIndex = 0;

			}

			var endIndex   = requestObject.count?(startIndex + requestObject.count):items.length;

			requestObject.abort = function(){

				aborted = true;

				if(oldAbortFunction){

					oldAbortFunction.call(requestObject);

				}

			};

			var scope = requestObject.scope || dojo.global;

			if(!requestObject.store){

				requestObject.store = self;

			}

			if(requestObject.onBegin){

				requestObject.onBegin.call(scope, items.length, requestObject);

			}

			if(requestObject.sort){

				items.sort(dojo.data.util.sorter.createSortFunction(requestObject.sort, self));

			}

			if(requestObject.onItem){

				for(var i = startIndex; (i < items.length) && (i < endIndex); ++i){

					var item = items[i];

					if(!aborted){

						requestObject.onItem.call(scope, item, requestObject);

					}

				}

			}

			if(requestObject.onComplete && !aborted){

				var subset = null;

				if (!requestObject.onItem) {

					subset = items.slice(startIndex, endIndex);

				}

				requestObject.onComplete.call(scope, subset, requestObject);

			}

		};

		this._fetchItems(request, _fetchHandler, _errorHandler);

		return request;	// Object

	},

	getFeatures: function(){

		return this._features;

	},

	close: function(/*dojo.data.api.Request || keywordArgs || null */ request){

		// I have no idea if this is really needed ...

	},

	getLabel: function(/* item */ item){

		// Override it to return whatever the label shall be, see Read-API.

		return undefined;

	},

	getLabelAttributes: function(/* item */ item){

		return null;

	},

	_fetchItems: function(request, fetchHandler, errorHandler){

		//	summary:

		// 		The request contains the data as defined in the Read-API.

		// 		Additionally there is following keyword "serverQuery".

		//

		//	The *serverQuery* parameter, optional.

		//		This parameter contains the data that will be sent to the server.

		//		If this parameter is not given the parameter "query"'s

		//		data are sent to the server. This is done for some reasons:

		//		- to specify explicitly which data are sent to the server, they

		//		  might also be a mix of what is contained in "query", "queryOptions"

		//		  and the paging parameters "start" and "count" or may be even

		//		  completely different things.

		//		- don't modify the request.query data, so the interface using this

		//		  store can rely on unmodified data, as the combobox dijit currently

		//		  does it, it compares if the query has changed

		//		- request.query is required by the Read-API

		//

		// 		I.e. the following examples might be sent via GET:

		//		  fetch({query:{name:"abc"}, queryOptions:{ignoreCase:true}})

		//		  the URL will become:   /url.php?name=abc

		//

		//		  fetch({serverQuery:{q:"abc", c:true}, query:{name:"abc"}, queryOptions:{ignoreCase:true}})

		//		  the URL will become:   /url.php?q=abc&c=true

		//		  // The serverQuery-parameter has overruled the query-parameter

		//		  // but the query parameter stays untouched, but is not sent to the server!

		//		  // The serverQuery contains more data than the query, so they might differ!

		//

		var serverQuery = request.serverQuery || request.query || {};

		//Need to add start and count

		if(!this.doClientPaging){

			serverQuery.start = request.start || 0;

			// Count might not be sent if not given.

			if (request.count) {

				serverQuery.count = request.count;

			}

		}

		// Compare the last query and the current query by simply json-encoding them,

		// so we dont have to do any deep object compare ... is there some dojo.areObjectsEqual()???

		if(this.doClientPaging && this._lastServerQuery!==null &&

			dojo.toJson(serverQuery)==dojo.toJson(this._lastServerQuery)

			){

			fetchHandler(this._items, request);

		}else{

			var xhrFunc = this.requestMethod.toLowerCase()=="post" ? dojo.xhrPost : dojo.xhrGet;

			var xhrHandler = xhrFunc({url:this.url, handleAs:"json-comment-optional", content:serverQuery});

			xhrHandler.addCallback(dojo.hitch(this, function(data){

				data=this._filterResponse(data);

				this._items = [];

				// Store a ref to "this" in each item, so we can simply check if an item

				// really origins form here (idea is from ItemFileReadStore, I just don't know

				// how efficient the real storage use, garbage collection effort, etc. is).

				dojo.forEach(data.items,function(e){

					this._items.push({i:e, r:this});

				},this);

				var identifier = data.identifier;

				this._itemsByIdentity = {};

				if(identifier){

					this._identifier = identifier;

					for(i = 0; i < this._items.length; ++i){

						var item = this._items[i].i;

						var identity = item[identifier];

						if(!this._itemsByIdentity[identity]){

							this._itemsByIdentity[identity] = item;

						}else{

							throw new Error("dojo.data.QueryReadStore:  The json data as specified by: [" + this.url + "] is malformed.  Items within the list have identifier: [" + identifier + "].  Value collided: [" + identity + "]");

						}

					}

				}else{

					this._identifier = Number;

					for(i = 0; i < this._items.length; ++i){

						this._items[i].n = i;

					}

				}

				// TODO actually we should do the same as dojo.data.ItemFileReadStore._getItemsFromLoadedData() to sanitize

				// (does it really sanititze them) and store the data optimal. should we? for security reasons???

				fetchHandler(this._items, request);

			}));

			xhrHandler.addErrback(function(error){

				errorHandler(error, request);

			});

			// Generate the hash using the time in milliseconds and a randon number.

			// Since Math.randon() returns something like: 0.23453463, we just remove the "0."

			// probably just for esthetic reasons :-).

			this.lastRequestHash = new Date().getTime()+"-"+String(Math.random()).substring(2);

			this._lastServerQuery = dojo.mixin({}, serverQuery);

		}

	},

	_filterResponse: function(data){

		//	summary:

		//		If the data from servers needs to be processed before it can be processed by this

		//		store, then this function should be re-implemented in subclass. This default

		//		implementation just return the data unchanged.

		//	data:

		//		The data received from server

		return data;

	},

	_assertIsItem: function(/* item */ item){

		//	summary:

		//		It throws an error if item is not valid, so you can call it in every method that needs to

		//		throw an error when item is invalid.

		//	item:

		//		The item to test for being contained by the store.

		if(!this.isItem(item)){

			throw new dojox.data.QueryReadStore.InvalidItemError(this._className+": a function was passed an item argument that was not an item");

		}

	},

	_assertIsAttribute: function(/* attribute-name-string */ attribute){

		//	summary:

		//		This function tests whether the item passed in is indeed a valid 'attribute' like type for the store.

		//	attribute:

		//		The attribute to test for being contained by the store.

		if(typeof attribute !== "string"){

			throw new dojox.data.QueryReadStore.InvalidAttributeError(this._className+": '"+attribute+"' is not a valid attribute identifier.");

		}

	},

	fetchItemByIdentity: function(/* Object */ keywordArgs){

		//	summary:

		//		See dojo.data.api.Identity.fetchItemByIdentity()

		// See if we have already loaded the item with that id

		// In case there hasn't been a fetch yet, _itemsByIdentity is null

		// and thus a fetch will be triggered below.

		if(this._itemsByIdentity){

			var item = this._itemsByIdentity[keywordArgs.identity];

			if(!(item === undefined)){

				if(keywordArgs.onItem){

					var scope =  keywordArgs.scope?keywordArgs.scope:dojo.global;

					keywordArgs.onItem.call(scope, {i:item, r:this});

				}

				return;

			}

		}

		// Otherwise we need to go remote

		// Set up error handler

		var _errorHandler = function(errorData, requestObject){

			var scope =  keywordArgs.scope?keywordArgs.scope:dojo.global;

			if(keywordArgs.onError){

				keywordArgs.onError.call(scope, error);

			}

		};

		// Set up fetch handler

		var _fetchHandler = function(items, requestObject){

			var scope =  keywordArgs.scope?keywordArgs.scope:dojo.global;

			try{

				// There is supposed to be only one result

				var item = null;

				if(items && items.length == 1){

					item = items[0];

				}

				// If no item was found, item is still null and we'll

				// fire the onItem event with the null here

				if(keywordArgs.onItem){

					keywordArgs.onItem.call(scope, item);

				}

			}catch(error){

				if(keywordArgs.onError){

					keywordArgs.onError.call(scope, error);

				}

			}

		};

		// Construct query

		var request = {serverQuery:{id:keywordArgs.identity}};

		// Dispatch query

		this._fetchItems(request, _fetchHandler, _errorHandler);

	},

	getIdentity: function(/* item */ item){

		//	summary:

		//		See dojo.data.api.Identity.getIdentity()

		var identifier = null;

		if(this._identifier === Number){

			identifier = item.n; // Number

		}else{

			identifier = item.i[this._identifier];

		}

		return identifier;

	},

	getIdentityAttributes: function(/* item */ item){

		//	summary:

		//		See dojo.data.api.Identity.getIdentityAttributes()

		return [this._identifier];

	}

});

dojo.declare("dojox.data.QueryReadStore.InvalidItemError", Error, {});

dojo.declare("dojox.data.QueryReadStore.InvalidAttributeError", Error, {});

}